Tunnel du Siaix on N90 Aime to Moutiers, French Alps


Anyone who's wanted to cycle from Aime to Moutiers in the Isere valley between Bourg St Maurice and Albertville will probably have been put off by the necessity of riding through the mile-long Tunnel du Siaix, or at least suffered the rather unpleasant experience of negotiating the tunnel if they weren't put off. The only alternative routes involve thundering great climbs up the sides of the valley.

The tunnel is usually busy, noisy, and car/van/lorry traffic skims past at 50+mph just a few inches away from the cycle lane on each side of the road with nothing to stop a wayward driver from running into the back of you.

Well, all that's changed for cyclists. Gone are the cycle lanes and cycling in the tunnel is banned - now cyclists are required to use a new dedicated additional tunnel adjacent/parallel to the main one, which is designated for cyclist/pedestrian use and also intended as a service tunnel and escape route for the main tunnel in case of fire.

Cyclists heading west need to get off the N90 at Centron, and find the lane that drops down the valley, under the railway, and then climbs back up a fair ascent to the new tunnel entrance, which is alongside the main entrance but not accessible directly from the N90 due to gates which are likely to be locked. Once through the downhill-trending tunnel, which is a lot cooler than the external temperature in summer, the exit is near the main western portal, but cyclists continue for several hundred metres along a shiny new, smooth cycle path before turning right to rejoin the N90 and thence proceeding as before to Moutiers.

Altogether a much improved experience. And today I took advantage of the new routeing to do the Bourg-Moutiers-Albertville-Beaufort-Cormet de Roselend-Bourg circuit, a hefty old ride. The new alignments and routeing can be seen HERE

Additional local news. Anyone who's ridden up the south-eastern ascent of the Cormet de Roselend from Bourg will have noticed the slightly oppressive abandoned semi-built hotel right by the roadside at Bonneval-les-Bains. I first cycled past this in 1988, and didn't pay any great attention but assumed it was some sort of derelict old army barracks or something, and only found out the story about it many years later. Anyway, it's recently been demolished.

All change here in the Isere valley area! Not least with some serious mudslides too following last week's storms that disrupted the Tour de France.
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